15.0
Fault Finding
50
© Baxi Heating UK Limited 2005
Low Electrical Supply
Incoming Voltage less than
180V. Check System Controls
& System Wiring. Otherwise
contact Electricity Provider.
Live & Neutral Reversed
Incoming Live and Neutral
reversed.
Wiring Harness
Ensure 8-way PCB
connector securely pushed
in. If fault persists replace
Wiring Harness.
Go to
Return Thermistor
section of the fault
finding instructions.
Go to
Flow Thermistor
section of the fault finding
instructions.
CH
works but
DHW
does not.
Go to
DHW Flow Switch
section of the fault
finding instructions.
DHW
works but
CH
does not.
Go to
DHW Fault
section of the fault finding
instructions.
Go to
Fan Lockout
section of the fault finding
instructions.
Go to
Ignition Lockout
section of the fault finding
instructions.
Go to
Overheat Lockout
section of the fault
finding instructions.
PCB Fault
Replace PCB.
YES
YES
YES
YES
YES
YES
YES
YES
YES
YES
YES
YES
YES
YES
Before performing fault finding carry out
preliminary electrical checks for earth,
continuity and polarity.
See Section 8.13
YES
Go to
Electrical Supply
section of the fault finding
instructions.
Low
High
ON
Reset
Low
High
Domestic Hot Water
LED Light - Green
Burner ON
LED Light - Green
Mains ON
LED Light - Green
Flame Failure
LED Light - Red
Off
Off
Off
Off
ON
LED
Lights
Off
On
Off
Flash
ON
LED
Lights
Go to
Dry-Fire
section of the fault finding
instructions.
Off
On
Flash
Flash
ON
LED
Lights
Off
On
Off
On
ON
LED
Lights
Off
Flash
Off
On
ON
LED
Lights
Off
Flash
Flash
On
ON
LED
Lights
On
On
Flash
On
ON
LED
Lights
Off
On
Flash
On
ON
LED
Lights
On
On
Flash
Flash
ON
LED
Lights
Off
Flash
Off
Flash
ON
LED
Lights
Off
On
On
On
ON
LED
Lights
Off
Flash
On
Flash
ON
LED
Lights
PCB Fault
Replace PCB.
PCB Fault
Replace PCB.
Off
On
On
Flash
ON
LED
Lights
Off
Flash
On
On
ON
LED
Lights
Go to
CH Fault
section of the fault finding
instructions.
YES